Originally uploaded by sciencedave
These two seed heads were spotted by Sam, my elder son, on a walk. He wanted to know if these were evidence of evolution. I admitted that I couldn't be certain, but that it seems likely to me. We talked a long time about how life must have gotten started, which is something that I have found interesting since I was a kid.
Once one understands the implications of evolution and abiogenesis, there is the problem of how life got started. I recall how fascinated I was when my dad told me about the Miller-Urey experiment, and I have continued to follow this a little. A.G. Cairns-Smith, who has suggested that early life, before DNA and RNA, might have been templated by clays is especially compelling to me, though it hasn't been widely accepted. It is, though, an attempt to wrestle with this difficult question of how life could get started. If it is totally wrong, it is still important because it tries to see the steps involved.
Professor Cairns-Smith was kind enough to send me some signed galleys of a chapter he wrote for a book on the origins of life that covered this back when I was a post-doc. I used them to prepare a lecture on the origin of life that my physicist advisor included as part of an intro astronomy class. It was great fun to tie the explosion of stars to clay to life to Steve Buscemi in 55 minutes...
Despite some of my organic friends alleged hatred for "icky metals", a lot of organic chemistry's contribution to biology is in holding an icky metal in just the right place to do something important. The interplay between all of science, especially when it comes to understanding what we are and why, is something that I am still trying to comprehend.